The mechanism of dextran biosynthesis by dextransucrase is being investigated by purifying the enzyme, insolublizing it on Bio-Ged beads and subjecting the system to pulse and chase experiments using C14-sucrose. Acceptor reactions involving low molecular weight carbohydrates e.g. glucose, fructose, maltose, isomaltose, and low molecular weight dextran are being studied. The nature of the acceptor products and their rates of formation are being studied.